Ring-shaped swimming aid for children and method of making the same



March 12, 1968 ROBERTSON 3,372,412

RINGSHAPED SWIMMING AID FOR CHILDREN AND METHOD OF MAKING THE SAME Filed Nov. 2l, 1966 N V E N TOR .dA MES H. ROBER7SON A G ZQAQ, Q

United States Patent 3,372,412 RING-SHAPED SWHVIMING AID FOR CHILDREN AND METHOD OF MAKING THE SAME James H. Robertson, 5238 Vineland Ave., North Hollywood, Calif. 91601 Filed Nov. 21, 1966, Ser. No. 595,708 6 Claims. ('Cl. 9-311) ABSTRACT OF THE DISCLOSURE A swimming aid for children and method of making such swimming aids of the type comprising a ring formed of molded lightweight material such as polystyrene foam. Disposed within the center of the ring is a relatively thin resilient diaphragm with an opening which fits around the body of the child adjacent to the armpits. A plurality of straps are connected between the ring and the body of thechild, extending over the shoulders of the child and being connected to the ring.

In order to prevent displacement of the straps and provide manufacturing economies and structural benefits, the straps are securely held to the ring by being molded into the ring at the time the ring is formed. The diaphragm in the-center of the ring may also have its outer edges molded into and held by the ring. The diaphragm preferably has openings through which the straps pass. The inner edge of the body receiving opening of the diaphragm is preferably serrated, to provide a more flexible and more secure grip upon the body of the child. The portion of the diaphragm which is molded into the ring may have a plurality of cuts forming triangular portions which are displaced transversely when the ring is molded, to increase the engagement between the diaphragm and the ring.

This invention relates to a ring-shaped swimming aid for small children and to a method for making the same.

My invention relates more particularly to a swimming aid of the type comprising a ring formed of rigid molded lightweight material, such as molded polystyrene foam. Disposed within the center of the ring is a relatively thin resilient diaphragm with an opening which fits around the body of the child adjacent to the armpits. A plurality of straps are connected between the ring and the body of the child, extending over the shoulders of the child and being connected to the ring.

It is among the objects of my invention to provide a swimming aid of the type described, and a method of making the same, in which the straps are securely held to the ring by being molded into the ring at the time the ring is formed.

This structure and method have numerous advantages, including simplicity, greater security in that the straps are firmly held and cannot come loose or work out of place, economy in that less strap material is required, and a more attractive appearance for the finished prodnot.

The diaphragm in the center of the ring may also have its outer edges molded into and held by the ring. The diaphragm preferably has openings through which the straps pass. The inner edge of the body receiving opening of the diaphragm is preferably serrated, to provide a more flexible and more secure grip upon the body of the child.

It is accordingly among the objects of my invention to provide a swimming aid for children and method of making the same having all of the advantages and benefits of the structure set forth above and described in further detail hereinafter.

My invention also comprises such other objects, advantages and capabilities as will later more fully appear and which are inherently possessed by my invention.

While I have shown in the accompanying drawings a preferred embodiment of my invention, it should be understood that the same is susceptible of modification and change without departing from the spirit of my invention.

Referring to the drawings,

FIG. 1 is a top plan view of a ring-shaped swimming aid constructed in accordance with my invention;

FIG. 2 is a sectional view of the same, taken along line 2-2 of FIG. 1;

FIG. 3 is a longitudinal sectional view of the lower part of the mold in which the ring is molded, showing the harness assembly in place prior to molding;

FIG. 4 is a longitudinal sectional view of both parts of the mold at the completion of the molding cycle;

FIG. 5 is a sectional view taken along line 55 of FIG. 1 showing one of the triangular cuts in the diaphragm.

A preferred embodiment which has been selected to illustrate my invention comprises a ring 10, which may be formed of any suitable material, but which is preferably formed of molded polystyrene foam.

The ring 10 is formed in a conventional two-part mold compirsing a stationary lower part 11 and a vertically movable upper part 12, which have complementary cavities 13 and 14 which define the shape of the ring 11). Two circular inner rings 13a and 14a and two concentric circular outer rings 13!) and 14b extend around the inner and outer edges of the cavities 13 and 14. A hydraulic piston or other suitable means is used to move the upper part 12 of the mold toward and away from the lower part 11.

At the beginning of a molding cycle, before the mold is closed, a harness assembly 15 is formed and mounted on a circular pin 16 which extends vertically upwardly from the center of the lower part 11 of the mold. The harness assembly 15 includes a resilient diaphragm 17, which is preferably formed of vinyl sheet material having a thickness of approximately ten thousandths of an inch, but other suitable types of materials and thicknesses may be used. The diaphragm 17 has an opening 18 at its center which is adapted to fit around the pin 16 to hold the harness assembly 15 in place.

A serrated score line 28 extends around the center of the diaphragm 17 in a somewhat oval or elliptical shape, slightly offset with respect to the opening 18'. Disposed around the entire outer peripheral edge of th diaphragm 17 are a plurality of spaced triangular scores or cuts 19, the apices of which are directed toward the center of the diaphragm 17. In the embodiment shown in the drawings, there are three concentric rows of triangular cuts 19, with the cuts in the inner and outer rows being aligned with each other and the cuts in the center row being oifset with respect to those in the inner and outer rows.

Directly inwardly from the inner row of cuts 19 are two pairs of elongated slots 20, which are disposed diametrically from each other. Extending through the slots 20 are four straps 21, which may be formed of any suitable material such as canvas or the like.

The outer ends of the straps 21 extend beneath the diaphragm 17' and then overlie and extend somewhat beyond the outer ring 13b of the lower part of the mold. The inner ends of the straps 21 extend inwardly through the slots 20 and over the inner ring 13a to adjacent the pin 16, where they overlie the diaphragm 17. The inner ends of two of the straps 21 may be provided with rings 22 at the ends thereof for removable attachment to the other two straps to hold the device on a child.

The ring 10 is then formed in a conventional manner,

using conventional molding techniques which are well known to those skilled in the art. In the case of polystyrene foam material, this comprises inserting polystyrene beads within the mold and expanding the beads with heat and water to fill the cavities 13 and 14.

Referring to FIG. 5 of the drawings, as the polystyrene beads expand, they cause the triangular portions of the diaphragm 17 which are defined by the cuts 19 to move in one direction or the other, so that the diaphragm 17 is more securely held against removal from between the two halves of the ring 10.

It will be noted that when the mold is closed by lowering the upper part 12 down upon the lower part 11, the rings 13a and 13b and the rings 14a and 14b are brought into engagement with each other, with the adjacent portions of the straps 21 and the peripheral portion of the diaphragm 17 being held between them.

When the ring is removed from the mold, the outer ends of the straps 21 may be cut off substantially flush with the outer periphery of the ring 10. The center of the diaphragm 17 may be removed along the score line 29, leaving an oval opening with a serrated edge which is adapted to fit around the body of a child.

The device is then complete and ready for use. It will be noted that no assembly is required after the molding operation, all of the parts being secured to the ring at the time it is formed. The outer ends of the straps 21 and the outer portion of the diaphragm 17 are securely held and virtually an integral part of the ring 10. It is accordingly impossible for the straps 21 to shift their location with respect to the ring 10, which shifting might result in harm to a child wearing the device. It is also impossible for the straps 21 to come off or become lost.

I claim:

1. The method of making a floating device comprising a ring formed of lighter than water material and a plurality of flexible straps secured to said ring, said ring being formed in a mold having a ring-shaped cavity, said mold being divided along a horizontal line into an upper part and a lower part, placing said straps so that a portion of each of said straps is disposed within said cavity prior to the molding of said ring, said straps extending across the upper edge of the lower part of said mold when said mold parts are in open position, said straps extending beyond the periphery of said cavity, closing said mold so that said straps are held between the parts of said mold during the molding of said ring, molding said ring around the portion of said straps disposed within said cavity, so that said straps extend through the transverse midportion of said ring after said ring is molded, with the portion of said straps which was disposed within said cavity being molded integrally within and securely held by said ring, the remaining portion of said straps being free, said straps being placed so that they extend substantially radially across said entire cavity, so that said straps extend radially through the entire midportion of said ring after said ring is molded.

2. The method described in claim 1, and providing a first pair of straps disposed adjacent to each other within one quadrant of said ring on one side of said ring and a second pair of straps disposed adjacent each other within the quadrant on the opposite side of said ring, the inner end of said straps extending substantially beyond the inner periphery of said cavity, so that said straps extend inwardly from the inner periphery of said ring after said ring is molded.

3. The method described in claim 2, and providing a thin diaphragm having its entire outer periphery disposed within said cavity before said ring is formed, said straps extending through openings in said diaphragm adjacent to the inner periphery of said ring, said diaphragm having a substantially oval serrated score line disposed adjacent its center, and removing the center portion of said diaphragm along said score line after said ring has been molded, to provide a substantially oval serrated opening within said ring adapted to fit around the body of a child.

4. The method described in claim 2, and providing a thin diaphragm having its entire periphery disposed within said cavity before said ring is formed, and providing the portion of said diaphragm which is disposed within said cavity with a plurality of triangular cuts, whereby the triangular portions of said diaphragm defined by said cuts are adapted to be displaced transversely with respect to said diaphragm when said ring is molded, to increase the inter-engagement between said diaphragm and said ring.

5. The method described in claim 4, and placing said straps so that the outer end of each of said straps extends beyond the outer periphery of said cavity and the inner end of said straps extends substantially beyond the inner periphery of said cavity, whereby a portion of the outer end of each of said straps extends beyond the outer periphery of said ring after said ring has been molded, and cutting off such portions substantially flush with the outer periphery of said ring, so that each of said straps extends across the entire width of said ring.

6. The method described in claim 5, and placing polystyrene beads within said cavity and expanding said beads to form said ring of polystyrene foam.

References Cited UNITED STATES PATENTS 2,724,843 11/ 1955 Kimball 9-347 3,032,789 5/1962 Fedorowicz 9340 3,095,586 7/1963 Baier 9-340 3,111,696 11/1963 Tolo 9340 3,137,015 6/1964 Lindeman '9340 FOREIGN PATENTS 982,601 2/1965 Great Britain.

MILTON BUCHLER, Primary Examiner.

T. W. BUCKMAN, Assistant Examiner. 

